CIE IGCSE Computer Science — Paper 1 (Theory)

Total marks: 75 · Duration: 105 minutes

Instructions to candidates

• Answer all questions in both Section A and Section B. • Write your answers in the spaces provided on the question paper. • You may use an HB pencil for any diagrams or graphs. • Calculators may be used but all working must be shown. • The number of marks is given in brackets [ ] at the end of each question or part question. • The total mark for this paper is 75. • Section A carries 45 marks and Section B carries 30 marks.

Paper

Section A — Structured Questions (45 marks)

Question 1

A school library uses a database management system to keep track of books and borrowers.

The library database contains two tables:

BOOKS table:

BORROWERS table:

(a) State what is meant by a primary key in a database table. [1]

(b) Identify a suitable primary key for the BOOKS table. [1]

(c) The library wants to create a third table called LOANS to record which borrower has borrowed which book.

(i) State two fields that should be included in the LOANS table. [2]

(ii) Explain why the LOANS table is needed rather than adding borrower information directly to the BOOKS table. [2]

(d) Write an SQL query to display the Title and Author of all books where the Genre is 'Non-fiction'. [3]

Question 2

A company is developing a mobile app that will store sensitive customer payment information.

(a) Describe what is meant by encryption. [2]

(b) The company decides to use symmetric encryption to protect the data.

(i) Explain how symmetric encryption works. [3]

(ii) State one advantage and one disadvantage of using symmetric encryption rather than asymmetric encryption. [2]

(c) The app will authenticate users before allowing access to payment information.

Describe two different methods of authentication that could be used, other than a simple password. [4]

Question 3

A programmer is writing a program to calculate the cost of cinema tickets.

The program uses the following rules:

• Standard ticket price is $12.00
• Children under 12 pay half price
• Senior citizens (65 and over) pay $8.00
• There is a $2.00 booking fee per transaction (not per ticket)

(a) Complete the following pseudocode algorithm to calculate the total cost for one ticket based on the age of the customer:

INPUT Age
IF Age < 12
   THEN Cost ← .............................
ELSE
   IF .............................
      THEN Cost ← 8.00
   ELSE
      Cost ← .............................
   ENDIF
ENDIF

[3]

(b) The programmer needs to extend the program to handle multiple tickets in one transaction and add the booking fee.

Write pseudocode to:

• Input the number of tickets required
• For each ticket, input the age and calculate the cost
• Calculate the total cost including the booking fee
• Output the total cost

You may use the algorithm from part (a) as part of your solution. [6]

(c) The program will be tested before being released.

(i) Explain the difference between syntax errors and logic errors. [2]

(ii) Suggest one test case that would help identify whether the booking fee is being calculated correctly. [2]

Question 4

A weather monitoring station collects temperature data every hour and transmits it to a central server.

(a) The temperature sensor produces an analogue signal.

(i) State what is meant by an analogue signal. [1]

(ii) Explain why the signal must be converted to digital form before being processed by a computer. [2]

(b) The system uses sensors to collect data automatically rather than requiring manual data entry.

State two advantages of using sensors for automatic data collection in this application. [2]

(c) Each temperature reading is stored as a real number with 32 bits of precision.

The monitoring station collects data 24 times per day (once per hour) for 365 days per year.

Calculate the total file size in megabytes (MB) needed to store one year of temperature data.

Show all your working. [4]

Question 5

A programmer is developing software using an iterative development approach.

(a) Describe what is meant by iterative development. [2]

(b) Compare iterative development with the waterfall model of software development. [4]

(c) The programmer writes the following pseudocode:

Counter ← 0
Total ← 0
REPEAT
   INPUT Number
   Total ← Total + Number
   Counter ← Counter + 1
UNTIL Counter = 10
Average ← Total / Counter
OUTPUT Average

(i) State what type of loop is being used in this algorithm. [1]

(ii) The programmer performs a dry run of the algorithm with the following input values: 5, 8, 12, 15, 20, 3, 7, 11, 9, 10

Complete the trace table for this algorithm:

[4]

Section B — Extended Response (30 marks)

Question 6

Modern vehicles contain many embedded systems that control various functions such as engine management, anti-lock braking systems (ABS), climate control, and entertainment systems.

(a) Explain what is meant by an embedded system. [2]

(b) Discuss the use of embedded systems in modern vehicles.

Your answer should include:

• The characteristics that make embedded systems suitable for vehicle control applications
• The advantages of using embedded systems in vehicles
• The potential risks and limitations of relying on embedded systems for critical vehicle functions
• How these risks might be managed

[12]

Question 7

A large online retailer stores customer data including names, addresses, purchase history, and payment card details.

(a) State two requirements of the Data Protection Act that the retailer must follow. [2]

(b) The retailer has experienced rapid growth and needs to upgrade its data storage infrastructure.

The IT department is considering whether to:

• Upgrade their existing on-site servers and storage systems, or
• Move to cloud-based storage and processing

Evaluate these two options for the online retailer.

Your answer should consider:

• Cost implications
• Scalability and performance
• Security and data protection
• Reliability and availability
• Control and management

You should make a justified recommendation for which option the retailer should choose. [14]